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New data on the age of the sedimentary infill of the Orava-Nowy Targ Basin : a case study of the Bystry Stream succession (Middle/Upper Miocene, Western Carpathians)

Wysocka A., Łoziński M., Śmigielski M., Czarniecka U., Bojanowski M.

Geological Quarterly

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2018

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Vol. 62, No. 2

327--343

EN

The Neogene sedimentary succession of the Orava-Nowy Targ Basin directly overlies the Central Carpathian Paleogene Basin deposits, the Magura Unit, and the Pieniny Klippen Belt. It provides an excellent geological record that postdates the main Mesoalpine structural and geomorphological processes in the Western Carpathians. Sedimentological, petrographical and geochronological investigations have allowed forthe re-examination of pyroclastic material, zircon dating, and a discussion on the relation of the Orava-Nowy Targ Basin to the exhumation of the Tatra Massif. The Bystry Stream succession is composed of NNW-inclined freshwater siltstones, sandstones and conglomerates. A few small, sometimes discontinuous, light grey intercalations of pyroclastic deposits and a single 1-2 m thick tuffite layer occur in the upper part of the succession. The tuffite contains an admixture of organic matter and siliciclastic grains (e.g., mica), suggesting that the volcanic ash fall was accompanied by normal deposition from weak currents. Sedimentation of deposits of the Bystry Stream succession took place in terrestrial settings, predominantly on floodplains and in rivers, in the vicinity of a hilly area supplying the basin with eroded material. The age of the tuffite layer from the Bystry Stream succession was determined at 11.87 +0.12/-0.24 Ma. The source of volcanogenic material in the tuffite was probably volcanic activity in the Inner Carpathians-Pannonian region, where effusive and volcanoclastic sillca-rich rocks were being produced by extrusive and explosive activity ~12 Ma. Obtained result connects the development of the Orava-Nowy Targ Basin at ~12 Ma with the late stage of the main episode of the Tatra Massif exhumation between ~22-10 Ma.

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The onset of orogenic activity recorded in the Krosno shales from the Grybów unit (Polish Outer Carpathians)

Bojanowski M.

Acta Geologica Polonica

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2007

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Vol. 57, no. 4

509-522

EN

The Krosno shales were deposited synorogenically in front of an accretionary prism as interchannel flysch facies on a north-dipping slope that constituted the southern marginal part of the Silesian basin. The turbidite flows originated from channelised currents and probably also as separate sedimentation events from slow, dilute "sheet" flows derived from a linear source (probably a shelf-edge). In the background continuous hemipelagic deposition took place and there were two periods when pelagic sedimentation prevailed. Mean accumulation rate of the entire succession was moderate: from 8 to 11 cm/ky. The source rocks were Jurassic to Eocene sedimentary rocks. Geochemical data (La, Th and Sc contents) point to a continental island arc as the original source of the detrital material. Soft-sediment deformations and methane-related authigenic carbonates that are also present in this succession evidence the migration of methane-charged fluids through the sediment column. This fluid expulsion was probably provoked by orogenic activity, i.e. the formation of an accretionary prism.

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Laminowane konkrecje węglanowe z łupków krośnień- skich w oknie tektonicznym Świątkowej Wielkiej (wschodnia część polskich Karpat zewnętrznych)

Bojanowski M.

Przegląd Geologiczny

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2001

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Vol. 49 nr 7

627-630

PL

Kilka typów konkrecji węglanowych zostało zebranych z łupków krośnieńskich (górny eocen-najwyższy oligocen). W niniejszej pracy opisane zostały najbardziej charakterystyczne - konkrecje laminowane. Posiadają one dyskoidalne i elipsoidalne kształty i składają się z dwóch typów lamin: brunatnych marglistych i szarych wapiennych. Oprócz mikrytowego kalcytu jako głównego składnika obu typów lamin, pierwszy typ zawiera także minerały ilaste (głównie illit) stłoczone pomiędzy kryształami kalcytu, podczas gdy drugi rozproszone ziarna kwarcu i dolomitu we frakcji mułowej. Wytrącający się z wód interstycjalnych kalcyt musiał najpierw spoić laminy luźnego osadu a następnie rozpychać poszczególne jego ziarna. Skorupki otwornic planktonicznych występują wyłącznie w obrębie lamin marglistych, ponieważ zostały zdeponowane wraz z zawiesiną frakcji ilastej. Laminy są równoległe na całej swej długości, co wskazuje na najwyżej nieznaczne tempo kompakcji podczas wzrostu konkrecji. Organizmy penetrujące osad docierały do konkrecji kiedy te były jeszcze miękkie ale już utworzone i składające się z obu typów lamin: marglistych i wapiennych. Ponadto dinocysty wypreparowane z konkrecji są wyjątkowo dobrze zachowane i nie posiadają oznak wpływu kompakcji. Tak więc badane konkrecje laminowane powstawały podczas przerwy w depozycji tuż pod dnem morza i uległy wczesnodiagenetycznej lityfikacji. Szczeliny septariowe powstały po wstępnym zlityfikowaniu konkrecji i następnie zostały wypełnione miodowym kalcytem.

EN

Several types of carbonate concretions were collected from the flysch Krosno shales (upper Eocene-uppermost Oligocene). This paper describes the most characteristic type - laminated concretions. They are discoidal to ellipsoidal in shape ami consist of two types of laminae: brown marly, and gray calcium carbonate ones. Apart from micritic calcite (principal constituent ot both types of laminae), the brown marly concretions consist also of clay minerals (mainly Mite) infilling calcite intergranular spaces. whereas the second type is highlighted by scattered aleuritic quartz and dolomite grains. The calcite precipitating from interstitial water must have originally cemented laminae ofloose host sediment and then displaced sediment grains. Planctonic joraminijer tests occur exclusively within the marly laminae because they were deposited together with suspended clayey particles. The laminae are parallel which indicates that the compaction rate during the growth of concretions was extremely slow. Yet, organisms penetrating the host sediment reached the concretions when they were still soft, but already formed and composed of these two types of laminae: marly, and calcium carbonate ones. Moreover, dinocysts, extracted from these concretions, are exceptionally well-preserved having apparently avoided compactional flattening. Therefore, the examined laminated concretions formed during a deposition break close to the water-sediment interface, and underwent early-diagenetic lithification. Septarian cracks were produced after primary: lithification, and subsequently filled with light brown calcite.